This topic describes the functional architecture of OceanBase Migration Service (OMS).
Service access layer
The service access layer manages migration tasks and various data sources and implements the O&M, monitoring, and alerts of all OMS components.
Process orchestration layer
The process orchestration layer manages the details for performing tasks such as upper-layer schema migration, full data migration or synchronization, incremental data migration or synchronization, data verification, data correction, and link switching.
Component layer
The component layer consists of the following components:
DBCat: accurately maps or converts data based on the source data type, destination data type, and character encoding type. The DBCat component is the native schema conversion engine of OceanBase Database and is the core schema migration component of OMS.
The DBCat component can convert and migrate various database objects such as tables, constraints, indexes, and views.
Store
The Store component reads raw data from the source instance, parses, filters, and formats the data, and persists the data on the local server.
Full-Import
The Full-Import component migrates existing data and synchronizes incremental data from tables in the source database.
Incr-Sync
The Incr-Sync component pulls incremental data from the Store component, filters the data based on the configured synchronization objects, and synchronizes the logs to the destination instance while ensuring the chronology and consistency of transactions.
Full-Verification
The Full-Verification component performs full-field verification on rows of the migrated tables and generates correction statements for inconsistent data.
The Supervisor component monitors the preceding components.